francis



(No Model.) 2 Sheets-Sheet 1.

J. G. FRANCIS. MAGNETO GENERATOR.

v No. 571,305. Patented Nov. 10, 1896.

wi/mw (No Model.) 2 Sheets-Sheet 2.

J. 0. FRANCIS.

MAGNETO GENERATOR. No. 571,305. Patented Nov. 10, 1896.

UNITED STATES PATENT Ornicn.

JOHN OHISHOLM FRANCIS, OF NElV YORK, N. Y., ASSIGNOR TO ELIAS M. GREENE,OF SAME PLACE.

MAGNETO-GENERATOR.

SPECIFICATION forming part of Letters Patent No. 571,305, dated November10, 1896. Application filed January 2, 1896. erial No. 574,126. Nomodel.)

To all whom it may concern:

Be it known that I, J OHN CHISHOLM FRAN- cIs, a citizen of the UnitedStates, residing in the city, county, and State of New York, haveinvented certain new and useful Improvements in Magneto-Generators, ofwhich the following is a specification.

This invention relates to electromagnetic generators; and it consistssubstantially in such features of improvement as will hereinafter bemore particularly described.

The invention has reference more particularly to that class ofelectromagnetic generators in which are embodied ordinaryhorseshoe-magnets, together with the usual armature rotating between thepoles orlower ends of the magnets, an automatic armature cut out, and abell or other similar call-signal.

The invention has forits object the simplification of construction ofthis class of devices generally, as well as to render the same verycompact, in order that the box may be materially reduced in size.

Afurther object of the invention is to ring up the call or signalwithout working through the high resistance offered by the armature andto automatically throw the armature into circuit, and to also insure thecentralization of the armature between the poles of the magnet.

Other objects of the invention will more fully hereinafter appear whentaken in connection with the accompanying drawings, wherein- Figure 1represents a front view in eleva tion, showing the call-box open andindicat ing very clearly the disposition or arrangement of the magnets,as well as the cut-out and the armature and bell circuits. Fig. 2 is asectional view, partly in elevation, to in dicate more clearly theconstruction and arrangement of parts. Fig. 3 is an end view to indicatemore clearly the construction and mode of operation of the automaticcut-out devices; and Fig. -l is a view in part eleva tion and in partsection, taken at right angles to Fig. 2 and representing more clearlythe construct-ion of the pole-pieces which 1 mm ploy in connection withmy improved electromagnetic generator. Fig. 5 is a detail view inperspective of a part of one of the pole pieces to more clearly indicatethe counterbore at the end to receive the head.

While my invention is capable of several different embodiments in use, Ipreferably resort to the construction and arrangement of partssubstantially such as 1 have herein illustrated in the accompanyingdrawings, wherein- 1, Fig. 1, represents the ordinary box or receptaclefor containing the generator and its appurtenances, and 2 is the usualdoor for closing the said box, the hinges 3 and at of said door beingutilized in this instance to complete the circuits. The bells or ringerdevices are preferably arranged to the outer side of the door 2, andtherefore they simply appear in dotted lines in Fig. 1. The usual orordinary form of magnetic coils 5 and (5 are employed to operate theordinary vibrating armature, (not shown,) which is caused to vibratebetween the bells in an obvions manner and thereby produce the sound orcall'signal.

The bell-circuit as well as the armature-circuit will be hereinaftermore specifically referred to in connection with the armature cutout andthe contacts, and therefore for the present we will leave the circuitsand proceed to describe the construction and arrangement of the saidgenerator and armature generally.

As shown in the several figures of the draw ings, there are fourhorseshoe-inagnets, (indicated,respectively,at 7, S, 9,and 10,) andthese are of the ordinary form, and which have been adopted owing totheir simplicity and the great convenience attached thereto.

In order not to have to bring the lower ends or poles of the magnets tooclose together by which to derive the desired effect produced by therotating armature, I preferably employ separate pole-pieces 11 and 12,(seen more plainly in Fig. 4,) and these polepieces are concaved ontheir inner faces by which the armature is centralized more perfectlybetween the poles, while at their lower ends the said pole-pieces areformed or pro vided with laterally-projecting feet 13, which projectbeneath the lower ends of the magnets and are in close contacttherewith. The faces of the pole-pieces, which rest against the poles ofthe magnets, are in very close contact with the latter, and in additionto the feet 13 of the pole-pieces increasing the contact-surface thesesaid feet serve also as arest for the lower ends of the magnets, andwhen the parts are put together or united, as hereinafter described, itwill be seen in what manner the said pole-pieces serve to maintain theproper relationship between the several parts or elements. The saidpole-pieces 11 and 12 are, furthermore, counterbored at each end betweencorners, as indicated at It, 15, 16, and 17, leaving curved edges orfaces, which, if continued around so as to join or connect each other,would constitute substantially a circular recess, and into this recessis inserted at each end of the generator a head 18, each being securedto the pole-pieces by means of suitable screws 19, or other similarfastening devices. The said heads serve between them to support theshaft 21 of the armature 22, which latter is of any suitable ordinaryform and which, as has been stated, rotates centrally of the lower endsof the magnets between the pole-pieces 11 and 12. At one end of thegenerator (shown in this instance at the left-hand side of Fig. 1) is anordinary bracket 24, in which one end of the shaft rests, and thisbracket or bridge, as it may be termed, is to allow sufficient room forthe accommodation of an ordinary collector 25, having heads 95, ofinsulating material, and which collector rotates with the shaft, andattached to the head 18 with which said bridge or bracket is formed isan insulated block 26, to which the colleetor-sprin 27 is secured by ascrew 28, the said spring being made to rest upon the collector in theusual or well-known way.

The pole-pieces 11 and 12 have each mounted thereon at each end of thegenerator a bracket 30, which between them serve as sup ports orbearings for the shaft 31, through the medium of which the automaticcut-out of the armature is effected. Carried by one end of the saidshaft is a large sprocketwheel 33 rigid with the shaft, and thissprocket-wheel is in movable connection with a small sprocket-pinion onthe corresponding end of the armature-shaft through the medium of asprocket-chain 238, the latterbeing normally maintained or held a littleslack for reasons as will hereinafter appear. \Vhile I employ this chainpreferably as a movable connection between the sprocket wheel andpinion, it is to be understood that I am not limited thereto in itsprecise form, since in some instances I may resort to the use of a wheeland pinion without sprockets, and in which case I could adopt anyordinary form of connecting belt or band having its outer surface formedat suitable distances apart with projections for effecting the resultsto be obtained, which results are to be more fully explained. Thepurpose is in the main to effect a cut-out of the armature-circuit for apurpose such as is well understood. I pre fer the use of the chain,however, since the same is exceedingly light and noiseless in operationand is always easily to be obtained at small cost.

The slack in the chain or band is taken up by a small degree of pressureexerted thereon at the point 36 by the upper end of a pivoted arm orlever 37, having its pivotal support at 38 in the corresponding head 18of the generator. The said lever is provided at its upper end with asmall roller 39, of rubber or other suitable material, while the lowerextremity thereof is bent outwardly at right angles to constitute alower projecting arm 4-0. A coiled spring 1-1 has its lower end attachedto the said projecting arm 10, while the upper end. of said spring isattached or fastened to a binding-screw 42, which. is inserted in aninsulating-block 43, attached to the corresponding bracket 30. Thetendency of the said spring is to maintain the said pivoted levernormally in the position shown in Fig. of the drawings, that is, withthe end of arm 40 thereof slightly elevated, and it is evident that whenthe shaft 31 is rotated by means of the crank 45, secured to the endthereof, the pulling side of the chain will straighten out, thus takingup the slack and forcing the roller 39 and lever 37 up, and consequentlylowering the end of arm 40. The said lower arm of the lever ispreferably provided at the end with a slightly-enlarged portion t7, theupper edge of which is normally in contact with the under surface of acontact-s in'ing 50, which latter is secured upon the upper part of aninsulating-block 52, arranged at one side of the central n1ag nets 8 and0 of the generator by means ofbinding-screws 5land Projecting from thepole-piece 11,l0cated at this side of the magnets, is a projectingportion 50, between which and the block 52 another contact-spring 57 issecured in place, this latter constituting a part of thearmature-circuit and normally being out of contact with any portion ofthe pivoted lover. The said pivoted lever may be variously constructedand arranged, but I prefer the arrangement shown, and it will beunderstood also that various changes could be made in the constructionand arrangement of the other parts referred to. The said lever isconnected in circuit through the medium of the coiled spring il, sinceattached or fastened to the same bimlingscrew 1-2, to which the upperend of said spring is connected, is a conductor a, properly insulatedand extending to a binding-post Z), thence to line.

An insulated wire connection 0 connects the spring 50 with thecollector-spring through screw 5i, and likewise a similar insulated wireconnection (Z leads from bincling serew of said spring, thence extendsto hinge i of the be); through metallic strip 6 and connection to coil(5 of the ringer-magnets, from coil (5 to coil 5, thence from the latterto hinge 3, connection h, and to ground.

From. this description it will be understood that when the handle orcrank is grasped and.

the sprocket-chain straightens out the arma' ture is automaticallythrown into circuit, and the bells will ring in the usual way byvibration of an ordinary ringer-armature pivotally supported between thetwo bells in any ordinary or well-known way.

It will be seen that normally the bell-movement is in circuit and readyto be rung up without having to work through the high resistance of thearmature, the circuit being through the binding-post b, conductor a,contact 42, spring 41, lever 37, spring 50, conductor d, hinge 4,conductors c f, bell-magneto 6 5, hinge 3, conductor h, to binding-postT, and to ground or line. I11 order to send a signal, the crank isoperated, and as soon as the chain is started the lever 37 is forcedagainst the spring 57 and the armature is connected in circuit and thesignal sent, and when the parts are allowed to come to a position ofrest the automatic cut-out of the an mature is effected by virtue of therestoration of the pivoted lever to its original position with the endof its arm 40 bearing against the under side of spring 50. In thusoperating the chain the circuit will be from line to binding-post Z9 andconductor a, contact 412, spring 41, to lever 37, to contact-spring 57,to projection 56 of pole-piece 11, through adjacent head 18, toarmature-shaft 21, to one end of the armature coil or winding, as usual,through said coil to the collector 25, to colleetorspring 27, toconnection 0, thence through connection d, via spring 50, to hinge 4c,strip e, and connector f, to coils 6 and 5 of ringer-magneto, andfinally to hinge 3 and connection it, to post '1, to ground or line, asthe case may be.

It will thus be seen in what manner my improved electromagneticgenerator is con structed and held together, and I desire it to beunderstood that I am not limited to the precise details of constructionherein shown and described. If desired, suitable screws or otherfastenings may be inserted into the urn der side of the pole pieces andmade to enter the lower ends of the magnets, so as to secure anadditional strength of structure, but for all ordinary purposes theyhave not been found to be necessary.

By notching or counterboring the ends of the pole-pieces in the mannershown and de scribed the heads serve to firmly and securely maintain therelation of said pole-pieces in that they cannot become readilyseparated, nor are they permitted from this construction to be forcedtogether in the act of bending or springing the ends of the permanentmagneto into place.

It will be further understood that I lay no claim herein to theparticular form or arran gement of the magnetic coils 5 and 6 whichoperate the bells, since they are of ordinary construction andarrangement, and are sim ply shown herein as a conventional. means bywhich to complete the description to a full understanding of myinvention.

lVithout limiting myself to the precise c011- struction and arrangementof parts shown, I claim as my invention 1. The combination in anelectromagnetic generator, of the contacts, the contact-lever, and aslack chain arranged to operate the lever when said chain is tightened,substantially as described.

2. The combination in an electromagnetic generator, of ordinaryhorseshoe -magnets, separate pole-pieces confined between the poles orlower ends of said magnets and counterbored at each end to constituterecesses for the reception of supporting heads or bearings for the shaftof the armature, substantially as described.

3. The combination in an electromagnetic generator, of separatepole-pieces confined between the poles or lower ends of the mag nets,heads recessed or sunken into the ends of said pole-pieces, andsupporting the rotating armature-shaft, brackets secured to the upperpart of the pole-pieces at their ends, a shaft supported in saidbrackets, a bell and armature circuit, and means for automaticallycutting out the armature, substantially as shown and described.

4. The combination in an electromagnetic generator,of ordinaryhorseshoe-magnets and an armature rotating between the lower ends of thelatter, a pinion carried by one end of the armature-shaft, an enlargedsprocketwheel supported in bearings above the pinion, and asprocket-chain connecting the two, and being normally somewhat slack,the pivoted lever normally pressing against the chain to take up theslack therein, and the coiled spring connecting the lower arm of saidlever, the whole being arranged substantially as shown and for thepurpose set forth.

5. The combination in an electromagnetic generator, of the separatepole-pieces, the armature-shaft, the pivoted lever, the enlargedsprocket-wheel and the sprocket-pinion, the connecting-chain, thecontact -springs, the coiled spring connecting the lever, and thearmature and bell circuits, substantially as shown and herein described.

6. The combination in an electromagnetic generator, of the pivotedlever, the upper contact-sprin g with which the lever is normally incontact, the lower contact-spring, constituting a part of thearmature-circuit, connections to complete both the armature-circuit withthe magnets and the bell-circuit, the bell-operating devices, and anautomatic device for operating said lever, substantially as shown andfor the purpose described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN CHISHOLllI FRANCIS.

Witnesses ARTHUR DELAPIERRE, P. G. SIMPSON.

